Can someone advise on collecting sap from frozen xylem vessels for metabolomics?

More Noam Reshef's questions See All

What is the best way to quantify cell number in tissues of developing flowers and fruits?

Assuming no endoreduplication.

04 May 2014 9,094 2 View

How can I neglect the effect of spatial soil differences in an outdoor agricultural field experiment?

Soil fertility seems to have a significant effect in my field experiment. I would like to neglect that to be able to focus on the varietal effect and check if it's significant or not.

09 October 2013 1,439 32 View

error in running a model in Abaqus

Excessive rotation of nodes in node set ErrNodeExcessRotation-Step1

17 August 2021 0 0 View

error in modelling model in Abaqus

Excessive rotation of nodes in node set ErrNodeExcessRotation-Step1

17 August 2021 0 0 View

MGL tools

20 June 2021 0 0 View

How climate change will influences human and animal behavioral change?

The role of climate change influencing the human behavior as well as economics interest

01 June 2021 0 0 View

flexibility of polymers chain

effect of double bond on the flexibility of polymers

07 April 2021 0 0 View

i have some problem with chtMultiRegionSimpleFoam

--> FOAM FATAL ERROR: Maximum number of iterations exceeded From function Foam::scalar Foam::species::thermo::T(Foam::scalar, Foam::scalar, Foam::scalar, Foam::scalar (Foam::species::thermo::*)(Foam::scalar, Foam::scalar) const, Foam::scalar (Foam::species::thermo::*)(Foam::scalar, Foam::scalar) const, Foam::scalar (Foam::species::thermo::*)(Foam::scalar) const) const [with Thermo = Foam::hConstThermo >; Type = Foam::sensibleEnthalpy; Foam::scalar = double; Foam::species::thermo = Foam::species::thermo >, Foam::sensibleEnthalpy>] in file /home/ubuntu/OpenFOAM/OpenFOAM-4.1/src/thermophysicalModels/specie/lnInclude/thermoI.H at line 66. FOAM aborting #0 Foam::error::printStack(Foam::Ostream&) at ??:? #1 Foam::error::abort() at ??:? #2 Foam::heRhoThermo >, Foam::sensibleEnthalpy> > > >::calculate() at ??:? #3 Foam::heRhoThermo >, Foam::sensibleEnthalpy> > > >::correct() at ??:? #4 ? at ??:? #5 __libc_start_main in "/lib/x86_64-linux-gnu/libc.so.6" #6 ? at ??:?

24 March 2021 0 0 View

Formulation of polymer color flakes

I am writing to request some information for making polymer color flakes. I would appreciate the help.

17 March 2021 0 0 View

What's the best way to measure growth rates in House sparrow chicks from day 2 to day 10?

What's the best way to measure growth rates in House sparrow chicks from day 2 to day 10? Since, the growth curve from day 2 to 10 won't be like the "Logistic curve" it might not follow logistic...

03 March 2021 1,401 3 View

What is the production process of CaFe ferroalloys?

I looking for ferro calcium production process

03 March 2021 1,755 4 View

Resistor definition in Piezoelectric bimorph with ANSYS workbench

Hello, good day! I am trying to simulate similar bimorph piezoelectric harvester with below commands. However, the output power doesn't change with resistor value. Please help to find the reason. ET,10,CIRCU94,0 !SET UP RESISTOR R,1,100000 !RESISTANCE VALUE TYPE,10 !SET ELEMENT TYPE E,1,2 !CREATE RESISTOR BETWEEN NODES 1 AND 2 Thanks in advance Regards,

02 March 2021 0 0 View

Guido Bongi

Each tissue has got its degrading enzymes from tubers to stem tissues wich are alive after twaving. I think you can measure the oxygen uptake, dephosphorylation or solution phenolics oxydations with twaving in action and then decide what is the case. Then you can try combinations of reductants like 2ME or more specific inhibitors like phenylmethyl sulphonyl fluoride (PMSF) or sacrifical proteins like serum albumine, or use trichloroactetic acid TCA, but all depends on what type of metabolite you want to be stable.

Ruzica Apostolova

I think that "defrosting procedure the enzymatic activity might effect the sample's metabolomic profile".. Is ok

Noam Reshef

Thank you Guido. There is a very wide range of metabolites that I'm interested in, from hormones to phenols and primary metabolites (metabolomics). In addition the samples might be used for miRNA analysis. As you can understand, there is a very wide range of metabolites that I want to protect from possible degradation. What is 2ME that you specified ?

Phillip: From field grown vines I cut shoots at about 30cm down from the apex. With a small knife I strip out the phloem tissue (which goes out very clean and easily on green, fresh shoots) and cut the remaining xylem (with pith) to 3-5cm pieces, wrap in aluminum foil and flash freeze it in liquid Nitrogen. The whole process takes about 1min.

Thank you Phillip.

The only contaminating live cells left in the samples are cells from the pith. A comparison between the centrifuge and a direct extract might reveal whether the centrifuge takes out the sap with minimal damage to the tissue cells. Using fresh tissues is a last resort since the process will take a long time and will probably lead to the degradation of sensitive metabolites as ABA.